In the semiconductor industry, the integration density within a die is growing rapidly. A die can include a huge amount of active and passive electronic devices so that a lot of functions can be performed within the die. The electronic devices are formed by semiconductor manufacturing processes on a silicon wafer. After the manufacturing processes of the electronic devices are finished, the wafer can be separated into many dies. Each die may then go through packaging processes so that a protection package is formed outside the die. The package for a die can also be an interface for connections between the die and a printed circuit board. Typical applications for integrated circuits include mobile phone systems, television systems, personal computer systems, and networking systems.
Many types of package have been developed, such as dual in-line pin package (DIP), quad flat package (QFP), ball grid array (BGA), and wafer level chip scale package (WLCSP). A DIP has connection pins on two parallel sides. DIPs usually use through-hole-mounting or sockets to be placed on printed circuit boards. DIPs usually comprise insulating materials filled around a metal lead frame.
A QFP usually has wing-like leads extending from four sides of the package. A QFP has connections only from the peripheral area of the package, so its pin count is limited. A BGA can use a whole surface to form an array of connections so that it can provide higher ball count. The length between the array of connections and the die is shorter, which is better for high speed signal transmission. A WLCSP can have a packaged device which is nearly the same size of a die. A WLCSP is generally smaller than a BGA package.